Petasites frigidus var. sagittatus (Banks ex Pursh) D. M. Cherniawsky

Petasites sagittatus (Banks) A. Gray, Bot. Calif. 1: 407. 1876
Tussilago sagittala Hanks; Pursh. PI. Am. Sept. 531. 1814. Nardosmia sagittal* 1<*>V 1! Bor.Am.l; 307. 1833.
;.'<! dentatu: Hlankinship. Mont. Agr. Coll. Stud. 1: 102. 1905.
A perennial, with a horizontal rootstock; scape 2-4 dm. high, floccose; scales lanceolate, attenuate, 5-8 cm. long; petiole* of the basal leaves i I dm. long; blades ovateor triangularsagittate, 5-25 cm. long, 4-20 cm. wide, dentate with numerous, broadly triangulai teeth, rarely mbentire, slightly floccose when young, soon glabrate above, irhite-tomentose beneath; inflorescence at first corytnbiform, in age much elongate; involucre of the hermaphrodite plant S-10 mm. high, 12-15 mm. broad; bracts 12-15, oblong, acutish; ray-flowers in a single series,
ligulate, apparently sterile; corolla-tube 4-5 mm. long, slender, the ligule spreading, 8-9 mm.
long, 2 mm. wide; disk-flowers numerous, sterile; tube 5 mm. long, the throat funnelform,
3 mm. long, the lobes lanceolate, 2 mm. long; anthers 3 mm. long; style-branches fusiform-
clavate above, with lanceolate branches; pappus 6-7 mm. long; involucre of the pistillate heads
7-8 mm. high, 8-10 mm. broad; flowers all or nearly all pistillate and fertile; corolla-tube
about 5 mm. long, the ligule erect, of the outer ones 3-4 mm. long, 1 mm. wide, of the inner
much smaller, rudimentary, or wanting; style-branches oblong; achenes 1.5-2 mm. long,
glabrous; pappus in anthesis 7-8 mm. long, in fruit up to 15 mm. long.
Type locality: Hudson Bay.
Distribution: Labrador to South Dakota, Colorado. British Columbia, and Alaska.